It is known that a number of substances perform an important role in the inflammatory process of the skin, such as acne, dermatoses such as, for example, psoriasis, eczema, and the like. These substances, including prostaglandins, hydroxyeicosatetraenoic acids, thromboxanes and leukotrienes, all have a common origin, namely arachidonic acid (see "VOORHEES, Leukotrienes and Other Lipoxygenase Products in the Pathogenesis and Therapy of Psoriasis and Other Dermatoses" Arch Dermatol. Vol. 119, July 1983, 541-547).
The formation of these substances results mainly from the release of arachidonic acid bound through an ester bond to the lipids present in the epidermis (for example the phospholipids).
For the treatment of skin diseases, prior recommendations have already been made to use either cyclooxygenase inhibitors, which inhibit prostaglandin formation, such as indomethacin, vitamin E, and the like, or substances capable of inhibiting lipoxygenases, such as eicosatetraynoic acid.
For the treatment of psoriasis, 5,8,11,14-eicosatetraynoic acid and also 5,8,11-eicosatriynoic acid, and their lower alkyl esters, have already been recommended (U.S. Pat. No. 4,190,669).